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Trinity College Dublin School of Chemistry 16 Dec 2009

Welcome To the Mass Spectrometry Unit Dr. Martin Feeney Room 0.5 Dr. J. Bernard Jean-Denis Chemistry building. Trinity College Dublin School of Chemistry 16 Dec 2009. Table of Contents.

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Trinity College Dublin School of Chemistry 16 Dec 2009

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  1. Welcome • To the • Mass Spectrometry Unit • Dr. Martin Feeney Room 0.5 • Dr. J. Bernard Jean-Denis Chemistry building Trinity College Dublin School of Chemistry 16 Dec 2009

  2. Table of Contents • Introduction to mass spectrometry 2 • 2. Sample Preparation 7 • a. Choice of Solvents • b. Sample Solubility • c. Sample Concentration • d. Sample Vials • e. Things to avoid in Sample Prep. • 3. Sample submission form 9 • a. Sample ID • b. Proposed Structure • c. Sample Handling/Storage • 4. Results 12 • 5. MS queries 13 Trinity College Dublin School of Chemistry p 1

  3. Introduction There are a number of instruments in the mass spectrometry facility of the School of chemistry that can offer a wide range of techniques and experiment types, such as MS/MS experiments or mass accuracy determination MS/MS experiments offers structural information of the molecule TOF, Time-of-flight ESI, Electrospray ionisation MALDI, Matrice assisted laser desorption ionisation LIT, Linear ion trap • Introduction to • mass spectrometry • a- ESI- TOF-MS • b- GC- TOF-MS • c- LDI-Q-TOF-MS • d- ESI-LIT-MS • Sample • preparation • Sample • submission form • 4. Results • 5. MS queries Trinity College Dublin School of Chemistry p 2

  4. Introduction ESI- TOF-MS • Introduction to • mass spectrometry • a- ESI- TOF-MS • b- GC- TOF-MS • c- LDI-Q-TOF-MS • d- ESI-LIT-MS • Sample • preparation • Sample • submission form • 4. Results • 5. MS queries ElectroSpray Ionisation coupled to Time-Of-Flight mass spectrometer Sample characteristics Charged or partially charged polar compounds. Sample might need ionisation agent, such as NaCl, Ammonium acetate,... Solvent choice -> see page 7 LCT Classic, Waters Principle An electric field sufficiently intense to disperse analyte solution emerging from the spray needle into a fine spray required a potential difference of up to sereval kV between that tip and the orifice leading into the vacuum system. The ions will be separate according to their mass-to-charge ratio through a TOF mass analyser before the determination of the accurate mass. References: Dole M et al., 1968. J. Chem. Phys., 49(5), p2240. Fenn JB et al., 1985. Anal. Chem., 57(3), pp675-679 Wiley WC & McLaren IH, 1955. Rev. Scientific Instruments, 26, (12), pp1150-1157. Trinity College Dublin School of Chemistry p 3

  5. Introduction GC- TOF-MS • Introduction to • mass spectrometry • a- ESI- TOF-MS • b- GC- TOF-MS • c- LDI-Q-TOF-MS • d- ESI-LIT-MS • Sample • preparation • Sample • submission form • 4. Results • 5. MS queries Gas Chromatography coupled to Time-Of-Flight mass spectrometer Sample characteristics Sample must be thermally volatile and stable Low mass range (typically lower than m/z 650) Solvent choice -> see page 7 GCT Premier, Waters Principle The sample coming from GC effluent could be ionised by three ionisation methods, which are EI (Electron Impact), CI (chemical Ionisation) and FD (Field desorption). The ions will be separate according to their mass-to-charge ratio through a TOF mass analyser before the determination of the accurate mass. References: Lampman GM et al., 2010.Spectroscopy, International Edition, 4thedition. Wiley WC & McLaren IH, 1955. Rev. Scientific Instruments, 26, (12), pp1150-1157. Trinity College Dublin School of Chemistry p 4

  6. Introduction LDI- TOF-MS • Introduction to • mass spectrometry • a- ESI- TOF-MS • b- GC- TOF-MS • c- LDI-Q-TOF-MS • d- ESI-LIT-MS • Sample • preparation • Sample • submission form • 4. Results • 5. MS queries Laser Desorption Ionisation coupled to Time-Of-Flight mass spectrometer Sample characteristics Generally speaking, samples which could not be ionised by ESI and non volatile Solvent choice -> see page 7 MALDI Q-TOF, Waters Principle The sample will be mix with a matrix*. Then, A laser will desorb the mixture and generate ions with high kinetic energy. The ions will be separate according to their mass-to-charge ratio through a TOF mass analyser before the determination of the accurate mass. MS/MS experiments can be done. Possibility of using ESI. * DCTB, CHCA, DIT, DHB. References: Lampman GM et al., 2010.Spectroscopy, International Edition, 4thedition. Wiley WC & McLaren IH, 1955. Rev. Scientific Instruments, 26, (12), pp1150-1157. Trinity College Dublin School of Chemistry p 5

  7. Introduction ESI- LIT-MS • Introduction to • mass spectrometry • a- ESI- TOF-MS • b- GC- TOF-MS • c- LDI-Q-TOF-MS • d- ESI-LIT-MS • Sample • preparation • Sample • submission form • 4. Results • 5. MS queries Electrospray ionisation coupled to a linear iontrap mass spectrometer Sample characteristics Charged or partially charged polar compounds. Sample might need ionisation agent, such as NaCl, Ammonium acetate,... Solvent choice -> see page 7 API 2000, Applied Biosystems Principle Quadrupole mass analysing device electric field is used to separate ions according to their mass-to-charge ratio as they pass along the central axis of four parallel equidistant metal rods that have fixed (DC) and alternating (RF) voltages. MSn , multiple MS/MS experiments can be done. References: Lampman GM et al., 2010.Spectroscopy, International Edition, 4thedition. Paul W, Reinhard HP & VonZahn U, 1958., Z. Phys., 152 (2), p143-182. Trinity College Dublin School of Chemistry p 6

  8. Sample Preparation • Introduction to • mass spectrometry • Sample • preparation • a- Choice of solvent • Sample solubility • b- Sample concentration • Sample vials • Sample • submission form • 4. Results • 5. MS queries Choice of solvent • Sample solubility • Sample must be fully dissolved. • In the event of partial solubility, filter or centrifuge the sample. Then, decant the supernatant to a clean vial for MS analysis. Trinity College Dublin School of Chemistry p 7

  9. Sample Preparation • Introduction to • mass spectrometry • Sample • preparation • a- Choice of solvent • Sample solubility • b- Sample concentration • Sample vials • Sample • submission form • 4. Results • 5. MS queries Sample concentration Mass Spectrometry is at least 20 times more sensitive than NMR. Do not submit the sample for MS straight from the NMR tube, please. Sample Vials Use 2 mL HPLC vials with dimension (12 x 32 mm (diameter x height)). Add anything between 0.5 to 1.5 mL solvent but please do not fill to the top of the vial. Things to Avoid in Sample Preparation: - salt buffers such as phosphates, citrates, borates, etc. - detergents - inorganic acids (H2SO4, H2PO4, etc) For HRMS, your sample must be pure. Trinity College Dublin School of Chemistry p 8

  10. Sample submission form One sample • Introduction to • mass spectrometry • Sample • preparation • Sample • submission form • a- One sample • b- More than one • sample • 4. Results • 5. MS queries Fill-in where there is a star  XXX XXX ZZZ ZZZ XXX@tcd.ie YYYY-MM-DD XXX 001 Draw the proposed structure, (see example in red) Exact Mass: 140.1201 Formula : C9H16O Do not forget to indicate the solvent of dilution X X X Trinity College Dublin School of Chemistry p 9

  11. Sample submission form More than one sample • Introduction to • mass spectrometry • Sample • preparation • Sample • submission form • a- One sample • b- More than one • sample • 4. Results • 5. MS queries XXX XXX ZZZ ZZZ XXX 001 XXX 002 XXX@tcd.ie YYYY-MM-DD 4 samples Exact Mass: 140.1201 Formula : C9H16O Exact Mass: 140.1565 Formula : C10H10 See Attachment XXX 004 XXX 003 X X Exact Mass: 140.1201 Formula : C9H16O Exact Mass: 142.1358 Formula : C9H16O X Trinity College Dublin School of Chemistry p 10

  12. Results • Introduction to • mass spectrometry • Sample • preparation • Sample • submission form • 4. Results • 5. MS queries Name (Supervisor), XXX 001 Experimental Mass Δm * Unsaturation degree Empirical formula Theoritical Mass Mass Accuracy ** Isotopic Pattern matching *, |Expected mass – Theoretical mass| * *, [Δm/(integer value of m)]x106 Trinity College Dublin School of Chemistry p 11

  13. MS queries • Introduction to • mass spectrometry • Sample • preparation • Sample • submission form • 4. Results • 5. MS queries Any questions regarding the mass spectrometry service in TCD then please askDr. Martin Feeney orDr. Bernard Jean-Denis. The mass spectrometry main lab phone number is 01-896 2768. If you would like to attend the MS course taught in the Dublin Chemistry programme, please contact Dr. Jimmy Muldoon. The course is usually scheduled for January-March of every year. Alternatively check the website: http://www.dublinchemistry.ie Trinity College Dublin School of Chemistry p 12

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